1. Field of the Invention
The present invention relates to a semiconductor device, an electroluminescent device and method of making the same, and more particularly, to a semiconductor device and an electroluminescent device in which the contact electrodes of one thin film transistor device and the doped gate electrode of another thin film transistor device are defined by the same patterned doped layer, and the method of making the same.
2. Description of the Prior Art
Compared with amorphous silicon thin film transistor (TFT) device, poly silicon TFT device has advanced electrical performance due to the high electrical mobility of poly silicon material. As the technique of lower temperature poly silicon (LTPS) process progresses, some main issues such as poor film uniformity of large area film have gradually been improved. Therefore, the LTPS process is expected to be applicable in large size substrate. In conventional LTPS process, the doped layer used to reduce the contact resistance of the TFT device is normally formed by ion implant process. However, there are technical problems required to be solved when introducing the implant apparatus to large size substrate process. For example, the cost of the implant apparatus for large size substrate process is extremely high. Thus, to form a doped layer with low resistance by anther approach is one of the main issues to be addressed.